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A096647
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Number of partitions of an n-set with even number of even blocks.
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0
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1, 1, 1, 2, 8, 27, 97, 443, 2095, 10440, 58194, 340375, 2097933, 13847485, 95504749, 690495874, 5245040408, 41428115543, 340899165549, 2917641580783, 25857170687507, 237421321934176, 2253720620740362, 22073206655954547
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,4
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FORMULA
| E.g.f.: exp(sinh(x))*cosh(cosh(x)-1).
a(n)=sum{k=0..n, if(mod(n-k,2)=0, A048993(n,k), 0)}; - Paul Barry (pbarry(AT)wit.ie), May 19 2006
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CROSSREFS
| Cf. A046682.
Sequence in context: A076884 A138388 A138386 * A054109 A150710 A150711
Adjacent sequences: A096644 A096645 A096646 * A096648 A096649 A096650
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KEYWORD
| easy,nonn
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AUTHOR
| Vladeta Jovovic (vladeta(AT)eunet.rs), Aug 14 2004
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EXTENSIONS
| More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Nov 16 2004
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